The long-term objective of this project is to develop a successful dental adhesive that will bond to enamel, dentin, and cementum and to restorative materials such as dental composites. There are seven specific aims which include: (1) to synthesize a series of dental adhesives based upon the newly developed alpha and beta isocyanatoacrylate monomers; (2) to characterize the basic chemical and physical nature of the polymers and/or copolymers which show promise as dental adhesives; (3) to perform initial biological screening tests on the potential dental adhesives; (4) to determine the strength and the characteristic of the adhesive blood with tooth structure; (5) to perform extensive biocompatibility and pulp studies on the potential dental adhesives; (6) to extensively characterize the interface between the dental adhesives and the tooth structure and between the dental adhesive and the composite filling material; and (7) to determine the feasibility of using the new dental adhesives as a luting agent for ceramic restorations. The project will encompass four major phases. The initial phase will involve refinement of specific polymer system of alpha and beta isocyantoacrylates. Those that show promise will be characterized by infrared spectroscopy, nuclear magnetic spectroscopy and differential scanning calorimetry to determine their chemical and physical nature. The second phase of the project will involve initial biocompatibility screening tests by using the 51Cr cytotoxicity test and implantation tests in rabbits. In addition, the bond strength will be determined by a shear test and the resulting fracture surface characterized with scanning electron microscopy. During the third phase of the project, more complete biocompatibility testing will be performed including pulp irritation tests in the primate, Macaca cynomologus and more complete bond testing including thermocycling studies. A fourth phase which will begin early in the study will involve extensive characterization of the chemical interaction of the proposed adhesive with tooth structure using Fourier transform infrared spectroscopy and transmission electron microscopy. The chemical interaction of current dental adhesives will also be characterized and compared with the newly developed adhesives.